This invention pertains to a mechanical means for preventing caulking and a flexible material as a filter screen, held down by the caulking from popping out of a groove in a flexible material or filter screen holder, particularly under the severe environmental conditions of continually changing temperatures between 200.degree. and 250.degree. F. under a minimum pressure of 200 psi.
This invention produced a vast and unobvious improvement over many prior trial runs. Various elastomers were tried, but all deteriorated rapidly. When trying glass filled Teflon caulking, the product would cause the glass to leach out of the glass filled Teflon. Various rubbers were utilized, but they all hardened eventually and were unsuccessful. Finally the disclosed mechanical means was discovered for retaining the caulking in the groove under the severe environmental conditions.